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Description of Business and Summary of Significant Accounting Policies - Additional Information (Detail) $ in Millions | 12 Months Ended
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Dec. 31, 2016 USD ($)
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |
Percentage of interest rate risk with rate floor | 50.00%
Days from origination after which mortgage loan are sold | 30 days
Loan upon which a default of principal or interest has existed for a period | 90 days
Gains on sale of other real estate owned | $ 1.2
Intangible assets, Estimated useful lives | 6 years 8 months 12 days
Core Deposit Intangibles [Member] |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |
Intangible assets, Estimated useful lives | 6 years 9 months 18 days
Minimum [Member] | Core Deposit Intangibles [Member] |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |
Intangible assets, Estimated useful lives | 7 years
Minimum [Member] | Customer Relationship Intangibles [Member] |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |
Intangible assets, Estimated useful lives | 3 years
Maximum [Member] | Core Deposit Intangibles [Member] |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |
Intangible assets, Estimated useful lives | 10 years
Maximum [Member] | Customer Relationship Intangibles [Member] |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |
Intangible assets, Estimated useful lives | 18 years
Home Equity Lines of Credit [Member] | Maximum [Member] |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |
Loans and finance receivables portfolio percentage | 8.00%
First Liens [Member] | Minimum [Member] |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |
Loans and finance receivables portfolio percentage | 82.00%
Junior Liens [Member] | Maximum [Member] |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |
Loans and finance receivables portfolio percentage | 10.00%

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- Definition The net gain (loss) resulting from sales and other disposals of other real estate owned, increases (decreases) in the valuation allowance for foreclosed real estate, and write-downs of other real estate owned after acquisition or physical possession. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.14(d)) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 + Details
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